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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
761

Aspects of nitrogen metabolism in the green alga Ulva: developing an indicator of seawater nitrogen loading

Barr, Neill G. January 2007 (has links)
The following research has focused on the utility of Ulva as an indicator of seawater nitrogen loading. Evaluation was made in three ways: 1) Observation of large-scale geographic variation in nitrogen status in natural populations around New Zealand in summer and winter, 2) Laboratory-based experimental assessment of the biochemical responses of N-indices in Ulva to nitrogen enrichment, and 3) Culturing standardized test-Ulva under low nutrient conditions which could be deployed into a variety of field situations. Seawater inorganic nutrient (nitrate, nitrite, ammonium and phosphate) concentrations and nitrogen (N)-indices (free amino acids, chlorophyll and total tissue nitrogen) in natural Ulva populations from 32 sites around New Zealand were compared. Sites were divided into 6 environmental categories: sheltered rural, exposed rural, rock pools, sheltered urban, exposed urban, and nitrogen-enriched urban sites. Seawater nutrient concentrations were highly variable between all sites in summer and winter. However, in the summer enriched urban sites had the highest mean total inorganic nitrogen concentrations and Ulva with the highest mean levels of all N-indices compared with any other environmental category. In the winter, Ulva contained more nitrogen (reflected in all N-indices) compared with Ulva in the summer, particularly in populations growing in colder southern seawater on more exposed coasts. The increase in Ulva N-status was not explained by increased seawater inorganic nitrogen concentrations. With univariate and multivariate statistical approaches it was shown that there was a significant effect of seawater temperature and site exposure on N-status in Ulva. Compared with other N-indices, stable nitrogen isotopes (δ15N) from Ulva growing in enriched urban sites had the widest range (4.77 ± 0.04 ‰ to 15.16 ± 0.03 ‰) of values compared with all other categories in both summer and winter. Conversely, Ulva from exposed rural sites had the lowest range of δ15N values compared with any other category (6.7 ± 0.1 to 8.8 ± 0.1 ‰) and showed no seasonal change in mean values (7.8 ‰ and 7.6 ‰ for summer and winter, respectively). In addition, δ15N values in Ulva were the only N-index that showed a significant difference between urban and rural categories. To test the relationship between inorganic nitrogen concentration in seawater and the responses of biochemical nitrogen indices in Ulva pertusa, several experiments were conducted in an outdoor, flow-through culture apparatus, in summer and winter. In this apparatus effects of ammonium concentration, nitrogen source (nitrate and ammonium), light and seawater motion were investigated. Of the same three N-indices examined in natural Ulva populations (free amino acids, chlorophyll and total tissue nitrogen), increases in free amino acids, particularly asparagine, provided the strongest indicator of increases in nitrogen availability. In addition, while tissue nitrogen and chlorophyll also increased with seawater nitrogen concentration, it was apparent that these indices were also strongly influenced by light, and probably season. Rates of ammonium assimilation provided no overall measure of the availability of nitrogen in seawater and were clearly affected by season. Similarly, growth rates in Ulva only showed a response to nitrogen addition in summer months. Stable isotopes of nitrogen (δ15N) in Ulva provided a clear distinction between natural and synthetic nitrogen sources, but more importantly, showed only minor fractionation (ranging from 1.3 ‰ to -1.9 ‰) of 15N supplied from synthetic nitrate and ammonium under both light-saturating and light-limiting conditions. To further develop Ulva as a standardized test-organism it was cultured in low-nutrient (non-polluted) seawater to deplete internal storage pools of nitrogen. Each month the resulting test-Ulva was then placed in surface-moored growth enclosures at a range of coastal sites around Auckland and then monitored for one year. In winter there were increases in seawater inorganic nitrogen concentrations and concomitant increases in free amino acid content. However, tissue nitrogen and chlorophyll content in test-Ulva showed similar increases (possibly saturating) across all sites suggesting that seasonal increases in these N-indices were also due to other seasonal factors (e.g., surface irradiance and / or seawater temperature). On the other hand, the total free amino acid pool showed strong differences between a low-nitrogen reference site and the other study sites all year round. It was probable that test-Ulva was integrating differences in tidally-averaged nitrogen loading that were not reliably detected in instantaneous seawater samples. In addition to N-indices in test-Ulva, levels of tissue heavy metals and stable isotopes of nitrogen showed strong differences with higher values of both typically found in urban environments compared with values found in non-polluted reference sites. It is concluded that several abiotic and biotic factors affect nitrogen status in Ulva, but the average nitrogen concentration in seawater, and the physical factors of temperature, light and water motion, appear to be the overarching determinants. It is further suggested that in combination with Ulva tissue δ15N values, tissue nitrogen and the free amino acid pool, as quantitative biochemical measures of nitrogen availability, are likely to provide useful information on both the amount and composition of nitrogen entering coastal environments. / Foundation for Research, Science and Technology. Auckland Regional Council.
762

Enriquecimento nutricional da mistura de bagaço de caju (Anacardium occidentale L.) e brotos de palma (Nopalea cochenilifera Salm-Dyck) por processos biotecnológicos para uso na alimentação humana. / Nutritional enrichment of the cashew bagasse mix (Anacardium occidentale L.) and palm shoots (Nopalea cochenilifera Salm-Dyck) by biotechnological processes for use in human food.

OLIVEIRA JÚNIOR, Geraldo Neves de. 05 June 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-06-05T16:12:57Z No. of bitstreams: 1 GERALDO NEVES OLIVEIRA JÚNIOR - DISSERTAÇÃO PPGSA PROFISSIONAL 2015..pdf: 1634063 bytes, checksum: 80e229d2b1f56448783db163d680a86e (MD5) / Made available in DSpace on 2018-06-05T16:12:57Z (GMT). No. of bitstreams: 1 GERALDO NEVES OLIVEIRA JÚNIOR - DISSERTAÇÃO PPGSA PROFISSIONAL 2015..pdf: 1634063 bytes, checksum: 80e229d2b1f56448783db163d680a86e (MD5) Previous issue date: 2015-12-18
763

Särskilt begåvade elever i matematikklassrummet : Hur kan lärare upptäcka, stimulera och utmana särskilt begåvade elever i matematik? / Giftedness in the mathematical classroom : How can teachers discover, stimulate and challenge gifted students in mathematics?

Gruvstad, Kim, Remes, Ebba January 2018 (has links)
Syftet med den här litteraturstudien är att ta reda på hur lärare upptäcker särskilt begåvade elever i ämnet matematik samt hur de stöttar och stimulerar dessa elever på bästa sätt. Syftet är också att göra lärare och pedagoger uppmärksamma på de särskilt begåvade elevernas uttryckssätt och behov. För att få fram relevant litteratur till vår studie har vi använt oss av metoderna databassökning och manuell sökning. Databaserna som vi har använt är ERIC, UniSearch och Google Scholar. Resultatet visar att elever med särskild begåvning kan uttrycka sig på många olika sätt vilket kan göra dessa elever svåridentifierade. Det finns karaktärsdrag hos de särbegåvade eleverna som är gemensamma för de flesta som till exempel motivation, kunskapstörst, nyfikenhet och god problemlösningsförmåga. Dock finns det även karaktärsdrag som ter sig olika från elev till elev, som till exempel förklaringsmetoder och social kompetens. Resultatet visar även vilka speciella behov särbegåvade elever har, samt didaktiska val som kan vara gynnsamma för de särbegåvade eleverna, exempelvis berikning, acceleration, gruppering och mentorskap.
764

The impact of job redesign on employee job outcomes: the case of the implementation of a private-public partnership model at a hospital

Onaga, Chukwuka Moses January 2015 (has links)
It has been widely reported that despite high health expenditure and a myriad of policies in place, South Africa’s health outcomes are worse than those in many lower income countries. The adverse health outcomes are even more pronounced in a rural province such as the Eastern Cape Province. Consequently, the Eastern Cape Department of Health (ECDOH) had turned to Private Public Partnerships (PPP) with the hope of mitigating some of the challenges beleaguering the health system in the province. This study evaluated the impact of the implementation of one of the PPP models at an Eastern Cape Hospital on key employee job outcomes. This is crucial as there had not yet, been this type of scientific assessment of the impact of the PPP model since the inception of the PPP about half a decade ago. Theoretical guidance of the study was provided by the Job Characteristics Theory (JCT) of Oldham and Hackman (1975), which predicted that changes in five core characteristics of a job will affect three critical psychological states which will in turn impact on key employee job outcomes. Uniquely, this study veered away from the traditional quantitative approach to the application of the JCT but rather adopted a qualitative case study approach. There is historical evidence that cross cultural validation of a theory in a new setting (a South African PPP hospital in this instance) benefits from an initial qualitative study. Data collection and analysis were guided by the JCT. Primary data collection was by semi-structured, face to face, one on one interviews. The analyses of the data specifically employed pattern matching and explanation building techniques, all underpinned by the JCT. Validity of interview data was strongly contributed to by available relevant case study documents. This study found that indeed, the implementation of this PPP model brought about changes in all five (JCT) core job characteristics of clinical staff, but to varying degrees in the three unique shared service areas. Interestingly, the three psychological states were found to have been impacted upon by changes in the JCT core job characteristics but also by factors related to the context of the job, such as quality of supervision and co-worker relationship. In contrast to the predictions of the JCT, this study also found that the key job outcomes were impacted directly by such contextual factors as the recent availability of specialists and staff shortages, among others. It also emerged that the PPP implementation has directly evoked a perception of inequity and breach of psychological contract among clinical staff working at the shared service areas. Among the three shared areas, the accident and emergency unit was discovered to have had the worst overall impact. Due to the importance of contextual factors at this PPP setting, key recommendations were directed towards improved management of the jobs. It is also recommended that a follow-up quantitative study be commissioned to further explore the main themes that emerged from this study. This research report is presented in three sections. Section 1 is the evaluative report itself, structured as an academic paper. Section 2 expands on the literature that was briefly reviewed in Section 1 while Section 3 outlines, in greater details, the research methods followed during the conduct of the research and the justifications thereof.
765

Loopbaanoriënteringsverrykingsprogram vir BSc (Agric)-studente aan die Universiteit van Pretoria / A career orientation enrichment programme for BSc (Agric)-students at the University of Pretoria

Malan, Francine 06 1900 (has links)
Text in Afrikaans / Die doel van die onderhawige studie is onder meer om loopbaanorientering aan die tersiere student (BSc Agric) teoreties te fundeer. 'n Uitgebreide Europese studiereis is ondemeem met die doel om bestaande loopbaanorienteringsprogramme aan tersiere instansies, veral universiteite, te ondersoek en die effektiwiteit daarvan te evalueer ten einde voortreflikhede te implementeer. In hierdie studie word die loopbaanorienteringsprogram vir BSc (Agric)studente aan die Universiteit van Pretoria wat reeds in 1994 ontwerp en ge'implementeer is, beskryf sowel as die behoeftepeiling wat onder BSc (Agric)-studente (voor en na die implementering van die program), en vennote in die landboubedryf gedoen is. 'n Verdere doel met die studie is om 'n wetenskaplik verantwoorde loopbaanorienteringsverrykingsprogram vir BSc (Agric)-studente aan die Universiteit van Pretoria te begrond, te ontwerp, die implementering daarvan te beskryf en die resultate daarvan te evalueer. Daar is gepoog om beide loopbaanontwikkelings- en studente-ontwikkelingsteoriee te beskryf en uit te le as fundering vir 'n verantwoorde loopbaanorienteringsverrykingsprogram vir tersiere studente. 'n Oorsig en perspektief is gebied op bestaande loopbaanorienteringsprogramme en -inisiatiewe in 'n intemasionale, nasionale en plaaslike konteks. Die verskynsel van die snelveranderende wereld-van-werk is literatuurmatig gepresiseer en die implikasies uitgewys vir die opleiding van en loopbaanorientering aan die student in die Landbouwetenskap. 'n Behoeftepeiling van loopbaan (en lewens-)kundighedeen vaardighede waaroor graduandi moet beskik is gedoen onder BSc (Agric)-studente (v66r en mi programimplementering) en onder vennote in die landboubedryf. Die ontwikkeling, beslaggewing en ,evaluering van 'n loopbaanorienteringsverrykingsprogram vir BSc (Agric)-studente is beskryf en toegelig. 'n Samevatting van die studie is gegee met enkele gemotiveerde aanbevelings wat uit die navorsing voortvloei. Voorstelle is gemaak vir die inisiering van 'n loopbaansentrum vir studente van die Universiteit van Pretoria. / The aim of this study is amongst others to lay the theoretical foundation of career orientation for BSc (Agric)-students. An extensive European study tour was undertaken with the aim of investigating and evaluating existing career orientation programmes and/or student enrichment endeavours at the various tertiary institutions especially universities. The effectiveness of these programmes was evaluated with the aim of utilizing and implementing aspects of them. In this study the career orientation enrichment programme for BSc (Agric)-students that was already designed and implemented at the University of Pretoria in 1994, is described. The needs of the BSc (Agric)-students before and after the implementation of this programme were determined as well as those of the partners in the agricultural industry. Another aim of this study is to describe the foundation, design and implementation of a scientific, accountable career orientation enrichment programme for BSc (Agric)-students at the University of Pretoria and to evaluate the outcome thereof. The various career development and student development theories are elucidated and described as a foundation for an accountable career orientation enrichment programme for tertiary students. An overview is given of career orientation programmes and initiatives in an international, national and local context. The phenomenon of the fast changing world-ofwork is described and defined more precisely through a literature study with reference to the implications for the training of and career orientation regarding the student in the Science of Agriculture. An investigation was done of the career (and life-) skills that graduates have to attain. The needs and views of BSc (Agric)-students (before and after the programme implementation) and partners in the agricultural industry were extracted. A summary is given of the arguments put forward in this thesis together with some recommendations that have emerged from this research. Proposals are made for the initiation of a career centre for students at the University of Pretoria. / Psychology of Education / D. Ed. (Sielkundige Opvoedkunde)
766

Applications of multinuclear solid-state NMR spectroscopy to the characterisation of industrial catalysts

Rankin, Andrew Gordon McLaughlin January 2018 (has links)
This thesis describes applications of advanced multinuclear solid-state nuclear magnetic resonance (NMR) experiments to the characterisation of industrially-relevant catalyst materials. Experiments on γ-Al₂O₃ introduce the use of solid-state NMR spectroscopy for the investigation of disordered solids. The existence of Al(V) sites on the surface of this material is demonstrated, showing that removal of adsorbed H₂O may facilitate a rearrangement effect in γ-Al₂O₃ that promotes the formation of these Al environments. A range of aluminium oxide-based supported metal catalysts has been investigated. Studies of these systems by ¹H and ²⁷Al solid-state NMR spectroscopy indicate that a metal-support interaction (MSI) exists between surface cobalt oxide crystallites and the γ-Al₂O₃ support, and is strongest for materials containing small, well dispersed Co oxide crystallites. It is shown that the hygroscopic nature of γ-Al₂O₃ allows the extent of the MSI to be visualised by ¹H MAS NMR, by observing the extent of the proton-metal oxide interaction resulting from the presence of adventitious adsorbed H₂O. The surface/bulk chemistry of Co spinel aluminate materials is also investigated. ¹H, ²⁹Si, ²⁷Al and ¹⁷O solid-state NMR techniques are used to gain insight into the structural nature of silicated alumina catalysts. The combination of isotopic enrichment and dynamic nuclear polarisation (DNP) surface-enhanced NMR spectroscopy can provide a definitive and fully quantitative description of the surface structure of Si-γ-Al₂O₃ (1.5 wt% Si), and the role of adventitious surface water is highlighted. Analysis of silicated aluminas prepared by “sequential grafting” and “single shot” approaches shows that silica growth on γ-Al₂O₃ follows two distinct morphologies. ¹⁷O gas exchange enrichment is also shown to be successful in facilitating ¹⁷O solid-state NMR studies of these materials. It is demonstrated that double (²⁹Si and ¹⁷O) enrichment of Si-γ-Al₂O₃ (1.5 wt% Si) can facilitate access to ²⁹Si-¹⁷O 2D correlation experiments, even at low silica loading. An exploratory investigation of Ti-alumina model catalysts has also been carried out using ¹H, ²⁷Al and ¹⁷O solid-state NMR spectroscopy. These studies indicate that Ti-γ-Al₂O₃ and Ti-Al M50 may be structurally distinct materials.
767

Efeitos da desnutrição protéica precoce e da estimulação ambiental em medidas bioquímicas e comportamentais em ratos / Effects of protein malnutrition early and environmental stimulation in biochemistry and behavioral measures in rats

Roberto de Oliveira Soares 06 April 2009 (has links)
O déficit na ingestão de proteína durante o período de rápido desenvolvimento do sistema nervoso central resulta em atrasos no desenvolvimento físico e cerebral, com conseqüências para o comportamento de ratos. Estudos mostram que prejuízos causados pela desnutrição podem ser parcialmente revertidos pelo enriquecimento ambiental e pela estimulação táctil. O enriquecimento ambiental aumenta a exploração no labirinto em cruz elevado (LCE), além de reverter alguns danos no cérebro de ratos desnutridos. O objetivo do presente trabalho foi comparar, em ratos desnutridos (D) e bem nutridos (C), os efeitos do enriquecimento ambiental (E) e da estimulação táctil (H) durante o período de formação do SNC (8 a 35 dias), através do desempenho no LCE aos 36 e 37 dias de idade. Os ratos foram divididos em dois diferentes grupos de acordo com a dieta: desnutridos (dieta com 6% de proteína) e controles (dieta com 16% de proteína). Também foram subdivididos em grupos conforme a manipulação ambiental: não estimulação (N), ambiente enriquecido (E), e estimulação táctil (H). A manipulação ambiental foi realizada nos períodos de 8 a 35 dias. Após os testes comportamentais os animais foram decapitados e tiveram o hipocampo e córtex occipital extraído para a análise de poliaminas através do método do HPLC, e o sangue foi retirado para a análise de corticosterona plasmática através da técnica de radioimunoensaio. Os dados evidenciaram que os animais D apresentaram menor peso corporal quando comparados com os animais C. A partir da exposição ao LCE, os resultados mostram que D permanecem uma maior porcentagem (p<0,05) de tempo e entram mais nos braços abertos em relação a C. Com relação às diferentes estimulações, os animais DE apresentaram uma menor percentagem (P<0,05) de tempo nos braços abertos quando comparados aos animais DH e animais DN. Os animais C apresentam uma atividade locomotora maior que D (p<0,05), demonstrado pelo maior numero de entradas nos braços fechados. Também foi possível verificar que D possui maiores níveis de corticosterona plasmática comparado a C. Também foi possível verificar que animais N possuem maior quantidade de espermidina (SPD), espermina (SPM) e SPD+SPM no hipocampo quando comparados com animais estimulados, independente da dieta a que foram expostos. Os dados do presente estudo sugerem que tanto a manipulação táctil como o enriquecimento ambiental amenizam as alterações produzidas pela desnutrição no comportamento de exploração dos braços abertos do LCE, além de alterarem a resposta de poliaminas no hipocampo durante a 2ª exposição ao LCE / Low protein ingestion during the brain growth spurt results in physical and cerebral deficits of development with long-lasting consequences for the behavior of rats. It has been show that impairments caused by protein malnutrition can be partially reverted by environmental enrichment and tactile stimulation. Environmental enrichment increases the exploration in the elevated plus-maze (EPM), and reverts some brain impairments produced by malnutrition. The objective of the present study was to compare effects of the environmental enrichment (E) and tactile stimulation (H) in malnourished (D) and well-nourished (C) rats, during the period of development of SNC (8 to 35 days), upon the behavior of rats in EPM at the ages of 36 and 37 days. The rats were divided in two different groups according to the diet: protein malnutrition (6% of protein) and controls (16% of protein). They were also subdivided according to the environmental manipulation: N, E and H. The environmental manipulation was accomplished from 8 to 35 days. After the behavioral tests, the rats were decapitated, and the hippocampus and occipital cortex removed for polyamines analysis by HPLC method, and the blood was collected for analysis of plasmatic corticosterone by radioimmunoassay technique. The results showed that D animals presented lower body weight than C animals. The EPM test showed that D animals enter and stay more time in the open arms than C animals (p<0.05). Regarding the different environmental stimulations, the DE animals presented a lower percentage of time in the open arms when compared to DH and DN animals (p<0.05). The C rats presents increases in the motor activity than D (p < 0.05), as demonstrated by higher number of closed arm entries Regarding the biochemical analysis it was showed higher levels of plasmatic corticosterone concentrations in D as compared to C animals. It was also showed that non-stimulated animals presented higher levels of spermidine (SPD), spermine (SPM) and SPD+SPM in the hippocampus when compared with stimulated ones, irrespective to the diet conditions. The present data suggest that both the tactile handling and the environmental enrichment reduced the behavioral alterations produced by early malnutrition in the exploration of the open arms in the EPM, as well as, altered the polyamines response in the hippocampus during the second trial in the EPM
768

Newsminer: um sistema de data warehouse baseado em texto de notícias / Newsminer: a data warehouse system based on news websites

Nogueira, Rodrigo Ramos 12 May 2017 (has links)
Submitted by Milena Rubi (milenarubi@ufscar.br) on 2017-10-09T14:12:56Z No. of bitstreams: 1 NOGUEIRA_Rodrigo_2017.pdf: 5427774 bytes, checksum: db8155583bf1bffe3ceb4c01bf26f66f (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-10-09T14:14:04Z (GMT) No. of bitstreams: 1 NOGUEIRA_Rodrigo_2017.pdf: 5427774 bytes, checksum: db8155583bf1bffe3ceb4c01bf26f66f (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-10-09T14:14:13Z (GMT) No. of bitstreams: 1 NOGUEIRA_Rodrigo_2017.pdf: 5427774 bytes, checksum: db8155583bf1bffe3ceb4c01bf26f66f (MD5) / Made available in DSpace on 2017-10-09T14:14:24Z (GMT). No. of bitstreams: 1 NOGUEIRA_Rodrigo_2017.pdf: 5427774 bytes, checksum: db8155583bf1bffe3ceb4c01bf26f66f (MD5) Previous issue date: 2017-05-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Data and text mining applications managing Web data have been the subject of recent research. In every case, data mining tasks need to work on clean, consistent, and integrated data for obtaining the best results. Thus, Data Warehouse environments are a valuable source of clean, integrated data for data mining applications. Data Warehouse technology has evolved to retrieve and process data from the Web. In particular, news websites are rich sources that can compose a linguistic corpus. By inserting corpus into a Data Warehousing environment, applications can take advantage of the flexibility that a multidimensional model and OLAP operations provide. Among the benefits are the navigation through the data, the selection of the part of the data considered relevant, data analysis at different levels of abstraction, and aggregation, disaggregation, rotation and filtering over any set of data. This paper presents Newsminer, a data warehouse environment, which provides a consistent and clean set of texts in the form of a multidimensional corpus for consumption by external applications and users. The proposal includes an architecture that integrates the gathering of news in real time, a semantic enrichment module as part of the ETL stage, which adds semantic properties to the data such as news category and POS-tagging annotation and the access to data cubes for consumption by applications and users. Two experiments were performed. The first experiment selects the best news classifier for the semantic enrichment module. The statistical analysis of the results indicated that the Perceptron classifier achieved the best results of F-measure, with a good result of computational time. The second experiment collected data to evaluate real-time news preprocessing. For the data set collected, the results indicated that it is possible to achieve online processing time. / As aplicações de mineração de dados e textos oriundos da Internet têm sido alvo de recentes pesquisas. E, em todos os casos, as tarefas de mineração de dados necessitam trabalhar sobre dados limpos, consistentes e integrados para obter os melhores resultados. Sendo assim, ambientes de Data Warehouse são uma valiosa fonte de dados limpos e integrados para as aplicações de mineração. A tecnologia de Data Warehouse tem evoluído no sentido de recuperar e tratar dados provenientes da Web. Em particular, os sites de notícias são fontes ricas em textos, que podem compor um corpus linguístico. Inserindo o corpus em um ambiente de Data Warehouse, as aplicações poderão tirar proveito da flexibilidade que um modelo multidimensional e as operações OLAP fornecem. Dentre as vantagens estão a navegação pelos dados, a seleção da parte dos dados considerados relevantes, a análise dos dados em diferentes níveis de abstração, e a agregação, desagregação, rotação e filtragem sobre qualquer conjunto de dados. Este trabalho apresenta o ambiente de Data Warehouse Newsminer, que fornece um conjunto de textos consistente e limpo, na forma de um corpus multidimensional para consumo por aplicações externas e usuários. A proposta inclui uma arquitetura que integra a coleta textos de notícias em tempo próximo do tempo real, um módulo de enriquecimento semântico como parte da etapa de ETL, que acrescenta propriedades semânticas aos dados coletados tais como a categoria da notícia e a anotação POS-tagging, e a disponibilização de cubos de dados para consumo por aplicações e usuários. Foram executados dois experimentos. O primeiro experimento é relacionado à escolha do melhor classificador de categorias das notícias do módulo de enriquecimento semântico. A análise estatística dos resultados indicou que o classificador Perceptron atingiu os melhores resultados de F-medida, com resultado bom de tempo de processamento. O segundo experimento coletou dados para avaliar o pré-processamento de notícias em tempo real. Para o conjunto de dados coletados, os resultados indicaram que é possível atingir tempo de processamento online. / OB800972
769

Efeito de diferentes intervenções domiciliares no desenvolvimento de crianças contaminadas por chumbo : um estudo longitudinal

Ribeiro, Máyra 26 February 2007 (has links)
Made available in DSpace on 2016-06-02T19:46:21Z (GMT). No. of bitstreams: 1 4920.pdf: 489498 bytes, checksum: 9e4b0d1ab8d50b5b6eaedfc2626327aa (MD5) Previous issue date: 2007-02-26 / Financiadora de Estudos e Projetos / Lead is a toxic metal that affects all the organs and systems of the human body, being its absorption bigger in children and pregnant women. Although the harmful effect of lead in infantile development (e.g., hyperactivity, cognitive deficit, low efficiency at school, etc) there are no studies on the effect of intervention programs for this population. The objectives of this work were: 1. to compare, the acquisition of abilities (foreseen in the Portage Guide) for children of 3 to 5 years old, with average level of lead equal to 21 &#61549;g/dl at four moments and 2. to verify the effect of two domiciliary interventions (A: individual training of the mother according to procedures of the Portage Guide, and the other, B: toys and models of tricks available to the child - environmental enrichment) in its performance. Two groups of 4 children were analyzed, being two groups of intervention and one of waiting control. The delineation counts on: evaluation retrospect (2002/03), a pre-test evaluation of all children in Portage Guide and HOME; implementation of the intervention programs with groups A and B (23 sessions); sounding the trained and emergent behaviors (application of the Portage Guide); retaken of the intervention program (9 weeks); post-test 1 (Portage Guide and HOME); post-test 2 (Portage Guide); post-test 3 with only one child of each group; besides the weekly evaluation of the children s performance through observation and record and posterior intervention with the controlled group. The results pointed to a decay of performance in the Portage Guide of evaluation 2002/03 for the pre-test, in the three groups, being the greater deficits in the cognition and language areas. After the period of intervention, children from group A got greater addition of behaviors, followed by group B and finally group C. The environment quality and care of these children came to be insufficient, but with improvements to the intervention for the submitted groups. It can be concluded that the two interventions speed up the development, but with better results for the intervention with parents guiding. The results indicate, also, that deficits of behavior tend to extend themselves throughout the time when it comes to this population. / O chumbo é um metal tóxico que afeta todos os órgãos e sistemas do corpo humano, sendo sua absorção maior em crianças e gestante. Apesar dos efeitos nocivos do chumbo no desenvolvimento infantil (ex., hiperatividade, déficit cognitivo, baixo rendimento escolar, etc) não existem estudos sobre o efeito de programas de intervenção para esta população. Os objetivos deste trabalho foram: 1.comparar, a aquisição de habilidades (previstas no Inventário Portage Operacionalizado - IPO) por crianças de 3 a 5 anos com nível médio de chumbo igual a 21 g/dl em quatro momentos e 2. verificar &#61549;&#61472;o efeito de duas intervenções domiciliares (A: treino individual da mãe segundo os procedimentos do IPO, e a outra B: disponibilização de brinquedos e modelos de brincadeiras à criança enriquecimento ambiental) no seu desempenho. Foram analisados três grupos de 4 crianças sendo dois grupos de intervenção e um de controle de espera. O delineamento conta com: avaliação retrospectiva (2002/03), uma avaliação pré-teste de todas as crianças no IPO e HOME; implementação dos programas de intervenção com os grupos A e B (23 sessões); sonda dos comportamentos treinados e emergentes (aplicação do IPO); retomada do programa de intervenção (9 semanas); pós-teste 1 (IPO e HOME); pós-teste 2 (IPO); pós-teste 3 com apenas 1 criança de cada grupo; além da avaliação semanal do desempenho das crianças via observação e registro e intervenção posterior com grupo controle. Os resultados apontam para queda de desempenho no IPO da avaliação 2002/03 para o pré-teste, nos 3 grupos, sendo os maiores deficits nas áreas de cognição e linguagem. Após o período de intervenção as crianças do grupo A obtiveram maior acréscimo de comportamentos, seguidas do grupo B e por último o grupo C. A qualidade do ambiente e cuidado destas crianças mostrou-se insuficiente, mas com melhoras para os grupos submetidos a intervenção. Pode-se concluir que as duas intervenções aceleram o desenvolvimento, mas com melhor resultado para a intervenção com orientação de pais. Os resultados indicam, também, que os deficits comportamentais tendem a se ampliar ao longo do tempo quando se trata desta população.
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Entrepôt de textes : de l'intégration à la modélisation multidimensionnelle de données textuelles / Text Warehouses : from the integration to the multidimensional modeling of textual data

Aknouche, Rachid 26 April 2014 (has links)
Le travail présenté dans ce mémoire vise à proposer des solutions aux problèmes d'entreposage des données textuelles. L'intérêt porté à ce type de données est motivé par le fait qu'elles ne peuvent être intégrées et entreposées par l'application de simples techniques employées dans les systèmes décisionnels actuels. Pour aborder cette problématique, nous avons proposé une démarche pour la construction d'entrepôts de textes. Elle couvre les principales phases d'un processus classique d'entreposage des données et utilise de nouvelles méthodes adaptées aux données textuelles. Dans ces travaux de thèse, nous nous sommes focalisés sur les deux premières phases qui sont l'intégration des données textuelles et leur modélisation multidimensionnelle. Pour mettre en place une solution d'intégration de ce type de données, nous avons eu recours aux techniques de recherche d'information (RI) et du traitement automatique du langage naturel (TALN). Pour cela, nous avons conçu un processus d'ETL (Extract-Transform-Load) adapté aux données textuelles. Il s'agit d'un framework d'intégration, nommé ETL-Text, qui permet de déployer différentes tâches d'extraction, de filtrage et de transformation des données textuelles originelles sous une forme leur permettant d'être entreposées. Certaines de ces tâches sont réalisées dans une approche, baptisée RICSH (Recherche d'information contextuelle par segmentation thématique de documents), de prétraitement et de recherche de données textuelles. D'autre part, l'organisation des données textuelles à des fins d'analyse est effectuée selon TWM (Text Warehouse Modelling), un nouveau modèle multidimensionnel adapté à ce type de données. Celui-ci étend le modèle en constellation classique pour prendre en charge la représentation des textes dans un environnement multidimensionnel. Dans TWM, il est défini une dimension sémantique conçue pour structurer les thèmes des documents et pour hiérarchiser les concepts sémantiques. Pour cela, TWM est adossé à une source sémantique externe, Wikipédia, en l'occurrence, pour traiter la partie sémantique du modèle. De plus, nous avons développé WikiCat, un outil pour alimenter la dimension sémantique de TWM avec des descripteurs sémantiques issus de Wikipédia. Ces deux dernières contributions complètent le framework ETL-Text pour constituer le dispositif d'entreposage des données textuelles. Pour valider nos différentes contributions, nous avons réalisé, en plus des travaux d'implémentation, une étude expérimentale pour chacune de nos propositions. Face au phénomène des données massives, nous avons développé dans le cadre d'une étude de cas des algorithmes de parallélisation des traitements en utilisant le paradigme MapReduce que nous avons testés dans l'environnement Hadoop. / The work, presented in this thesis, aims to propose solutions to the problems of textual data warehousing. The interest in the textual data is motivated by the fact that they cannot be integrated and warehoused by using the traditional applications and the current techniques of decision-making systems. In order to overcome this problem, we proposed a text warehouses approach which covers the main phases of a data warehousing process adapted to textual data. We focused specifically on the integration of textual data and their multidimensional modeling. For the textual data integration, we used information retrieval (IR) techniques and automatic natural language processing (NLP). Thus, we proposed an integration framework, called ETL-Text which is an ETL (Extract- Transform- Load) process suitable for textual data. The ETL-Text performs the extracting, filtering and transforming tasks of the original textual data in a form allowing them to be warehoused. Some of these tasks are performed in our RICSH approach (Contextual information retrieval by topics segmentation of documents) for pretreatment and textual data search. On the other hand, the organization of textual data for the analysis is carried out by our proposed TWM (Text Warehouse Modelling). It is a new multidimensional model suitable for textual data. It extends the classical constellation model to support the representation of textual data in a multidimensional environment. TWM includes a semantic dimension defined for structuring documents and topics by organizing the semantic concepts into a hierarchy. Also, we depend on a Wikipedia, as an external semantic source, to achieve the semantic part of the model. Furthermore, we developed WikiCat, which is a tool permit to feed the TWM semantic dimension with semantics descriptors from Wikipedia. These last two contributions complement the ETL-Text framework to establish the text warehouse device. To validate the different contributions, we performed, besides the implementation works, an experimental study for each model. For the emergence of large data, we developed, as part of a case study, a parallel processing algorithms using the MapReduce paradigm tested in the Apache Hadoop environment.

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